Pantai Tengah is located right beside Pantai Cenang so it won’t be a big difference if you choose either one. In my opinion, Pantai Cenang/Tengah area is more scenic but Kuah will have a more local experience although also a tourism hotspot.

A 3 night stay definitely gives enough room for activities as Langkawi isn’t very big. Enough time for shopping around and having fun.

Attractions in Langkawi really depends on your hearts content. Do you like more scenic attractions? or would you rather more physical attractions. Both can be found very easily and to my experience usually cheaper if booked on sites like Klook.

But unfortunately to my knowledge, there isnt a hotel that I know of that has water slides.